Continuous-Wave Green Laser of 9.9 W by Intracavity Frequency Doubling in Laser-Diode Single-End-Pumped Nd：YVO4／LBO

A maximum of 9.9 W cw TEM00 output at 532nm laser has been obtained by intracavity frequency doubling with LBO in laser-diode single-end-pumped Nd:YVO4. The Nd:YVO4/LBO green laser has a simple threemirror V-fold cavity structure. The optical-optical conversion efficiency was 34.8%. Based on the equation of thermal conduction, a general solution for the laser-crystal interior temperature distribution is obtained by the semi-analytical thermal analysis method. Using the software system, the cavity parameters have been optimized according to the stability condition and the astigmatic compensation principle. The astigmatism in the cavity has been effectively controlled and the resonator was insensitive to the thermal lens in the Nd:YVO4 crystal.     

准连续光抽运光子晶体光纤产生超连续谱中的调制不稳定性(英文)

报道了应用准连续光抽运光子晶体光纤产生超连续谱时的一种现象,并根据调制不稳定和数值解薛定谔方程证明此现象为调制不稳定性.在实验中发现有两个波峰,与中心波长之间的距离分别为27 .08 nm和32 .72 nm,经过对比和分析数值结算和实验结果非常吻合,说明调制不稳定性在准连续光抽运光子晶体光纤产生超连续谱过程中起着重要的作用.     

Dispersion measurement of Yb-doped fiber by a spectral interferometric technique

<正>The dispersion of Yb-doped fiber is measured by a spectral interferometric technique.The experimental verification is achieved by comparing the measured data with published data of the Nufern 1060xp fiber and the measurement relative error is 1.36%.The parameters of the experimental system,such as minimum required source bandwidth and minimum fiber length,are introduced and analyzed in the measurement. The minimum required source bandwidth predicted through theoretical calculation at the center wavelength of 1070 nm is 19.3 nm,which perfectly agrees with the experimental value.     

亚纳秒光脉冲抽运光子晶体光纤产生的瓦级超连续谱

研究了亚纳秒脉冲抽运光子晶体光纤产生高功率超连续谱的机理.采用掺镱锁模光纤激光器产生的脉宽570ps光脉冲,抽运1.8m光子晶体光纤,得到了平均功率为1.15W、光谱覆盖范围为750nm的超连续谱.通过实验和模拟结果的对比和分析,证实了亚纳秒脉冲抽运1.8m PCF产生超连续谱时,调制不稳定性效应起了重要作用.在研究了不同抽运功率下输出的超连续谱变化后,发现随着抽运功率的提高,输出功率也更高且超连续谱覆盖波段也更宽,在瓦级输出功率下依然未达到饱和展宽状态,还有进一步提高功率和展宽光谱的空间.     

低阈值展宽脉冲锁模掺Er3+光纤环形激光器的实验研究

将正色散值较小的掺铒光纤引入传统的环形腔构成了低阈值的展宽脉冲锁模激光器.通过使用这种掺铒光纤,激光器的锁模阈值大大降低,激光器的自起振泵浦功率仅为90 mW,而且在29 mW的低泵浦功率时仍然可维持稳定的锁模状态.实验中获得了脉冲宽度为175 fs,光谱半高宽为40 nm,重复频率为33 MHz的锁模脉冲输出.激光器工作稳定,光谱干净光滑.     

咪喹莫特的合成研究

在对咪喹莫特的合成方法综述的基础上,以4－羟基－2（1H）－喹啉酮为原料经硝化、氯代、胺取代、还原、环合、胺取代共六步反应合成了咪喹莫特。该过程适合于大规模操作。在以苄胺取代化合物V的4－位氯原子时,如以DMF为溶剂,则所得化合物不是Ⅶ而是Ⅷ。同样,以胺的DMF溶液与V反应也得到Ⅷ。Ⅶ的脱苄反应在所用的试验条件下未能发生。     

Theoretical analysis of the electromagnetic field inside an anomalous-dispersion microresonator under synthetical pump

We study the spatiotemporal evolution of the electromagnetic field inside a microresonator showing an anomalous dispersion at the pump wavelength by using the normalized Lugiato–Lefever equation. Unlike the traditional single continuous wave(CW) pumping, an additional pump source consisting of periodical pulse train with variable repetition rate is adopted.The influences of the microresonator properties and the pump parameters on the field evolution and the electromagnetic field profile are analyzed. The simulation results indicate that, in the anomalous dispersion regime, both increases of the input pulse amplitude and the repetition frequency can result in the field profiles consisting of multiple peaks. A series of equidistant pulses can also be obtained by increasing the CW pump power. In addition, we find that a large physical detuning between the pump laser carrier and the cavity resonance frequency also causes the splitting of the inside field.     

固相萃取-超临界流体色谱-质谱联用同时快速测定中成药和保健食品中的12种抗过敏化学药物

建立了固相萃取-超临界流体色谱-质谱联用（SPE-SFC-MS/MS）快速检测中成药和保健食品中12种抗过敏化学药物的分析方法。样品经甲醇超声提取,Oasis MCX固相萃取柱净化。采用Waters Trefoil CEL1色谱柱（150 mm×3.0 mm,2.5 μ m）,以CO₂为流动相A,甲醇-氨水（100：0.1,v/v）为流动相B,进行梯度洗脱。流速为1.2 mL/min,柱温和背压分别为45℃和12.4×10⁶ Pa。12种抗过敏化学药物以电喷雾离子源在正离子或负离子模式下用多反应监测（MRM）方式进行监测,整个分析过程在10 min内完成。结果表明,12种化学药物在5~250 μ g/L范围内线性关系良好,相关系数（r）均≥ 0.998,检出限（LOD）为0.141~0.262 μ g/L,定量限（LOQ）为0.703~1.308 μ g/L。3种加标水平（10、20和100 μ g/L）下,12种化学药物的平均回收率为76.1%~112.5%,相对标准偏差（RSD）为1.1%~8.3%。该法简便,灵敏性高,实用性强,可用于抗过敏类中成药和保健食品中非法添加抗过敏化学药物的检测。     

基于光纤中超短脉冲非线性传输机理与特定光谱选择技术的多波长飞秒激光的产生

高集成、高可靠性宽调谐飞秒激光源在超快光谱学、量子光学及生物成像等研究与应用领域具有重要价值.如在生物多光子显微成像中,具有适中能量的宽调谐飞秒激光源不仅可满足多种生物组织荧光激发所需的峰值功率与激发波长,而且也可以显著提升非线性荧光产生效率、成像分辨率以及增大成像穿透深度.采用自主研发的高可靠性全保偏光纤飞秒激光器作为抽运源,基于低色散光纤中高峰值功率飞秒激光脉冲非线性传输引起的光谱加宽机制,本文开展了多波长全光纤飞秒激光产生技术研究.通过采用中心波长在980, 1000,1050, 1070与1100 nm的带通滤波片选择性地对单模光纤输出光谱中最左边与最右边光谱旁瓣进行滤波,在上述中心波长处分别可获得203, 195, 196, 187与194 fs的激光输出.本文提出的基于全光纤飞秒激光脉冲在单模光纤中非线性传输引起的光谱加宽机制与特定光谱选择技术的实验方案为高集成、高可靠性宽调谐飞秒激光源的实现提供了新的研究途径.     

连续线性温度梯度场对啁啾脉冲放大系统中啁啾光纤光栅的色散调节效应

利用啁啾光纤光栅的温度可调谐效应,提出了一种新型的色散补偿方法.该方法使啁啾光纤光栅处于一个连续的线性温度梯度场中,通过调节啁啾光纤光栅两端的温度差,改变其色散量,实现在以啁啾光纤光栅为展宽器和以体光栅为压缩器的超快激光系统中对输出脉宽的连续精密调节,并通过实验验证这一方法的可行性.实验结果表明:沿着啁啾光纤光栅应用连续的温度梯度场,当温差从0℃到50℃变化时,可以连续地调节啁啾光纤光栅的色散参数.展宽器和压缩器之间的色散失配可以通过调节线性温度场的温度梯度得到补偿,避免了繁琐的脉宽优化步骤.本文是以啁啾体光栅为压缩器的光纤啁啾脉冲放大系统中通过调节施加在展宽器上的连续线性温度场的梯度,实现对啁啾脉冲系统中的色散失配进行精密调制的技术方案.